Hi folks,
This discussion topic has evolved from another one so I'm creating a new heading for it....
I'm doing live looping / playing with Mk3 and multiple external midi controllers.  I would like to be able to set up kits and instruments and switch back and forth between different instrument configurations using the same external midi controllers when performing / composing / looping.  
So I have two external midi controllers I'm using (Handsonic HPD-20 and a JamKat from Alternate Mode).  I'm a percussionist so these are useful / versatile and allow me to use a combination of hands / sticks to generate the rhythms I want to layer while then using the Mk3 keypad for things like bass lines / drones / keys - more tonal stuff.
Let's say in Group 1 I have two instruments - each controlled with a separate midi controller.  Easy enough.  After laying down the basic track then I want to switch to group 2 and using the same controllers layer in two additional instruments.  Here's where it gets tricky.  
At this point I need to route the signal from the midi controllers (their midi out) in such a way as to only play the instruments in group 2 now.  To my knowledge based on help from the first discussion, I need to put those instruments in group 2 on a separate midi channel from the ones in group 1 - and then take the midi outs from each controller and switch those to the same channel.  That way when I play Group 2 it's only Group 2 that gets added to the mix.  If I want to go back to Group 1 I need to switch back to the midi channel controlling Group 1's instruments.  
What's kinda frustrating is that NI has figured out a way to ensure that when you play the pads in each group it doesn't activate the sounds in the other groups.  I want to achieve this same level of control over Group instrumentation - but with external midi controllers.  
I hope that makes sense.  
Thanks for any input / suggestions (including any software or gear you might suggest that would do this on a Mac M1 running OS 11 or higher). 
Cheers,
Stephen